Safety retract mechanism

ABSTRACT

A safety retract mechanism for a transfer device which indexes workpieces between successive stations in a press-mounted die. The safety retract is actuated by the press ram to remove the work-gripping elements of the transfer device from the die should the usual drive arrangement for these elements be rendered inoperative.

United States Patent 1191 [111 3,746,184

Wallis July 17, 1973 1 SAFETY RETRACT MECHANlSM 3,411,636 11/1968 Wallis214 1 BB [76] Inventor: Bernard J. Wallis, 25200 Trpwbrldge Avenue-Dearborm Primary ExaminerGerald M. Forlenza Assistant ExamineF-George F.Abraham [22] Filed; J l 26, 1971 Attorney-Barnes, Kisselle, Raisch &Choate [2!] Appl. No.: 166,280

Related US. Application Data [57] ABSTRACT [63] Continuation-impart ofSer. No. 67,843, Aug. 28,

1970, abandoned- A safety retract mechanism for a transfer device whichindexes workpieces between successive stations in a [52] US. Cl. 214/1BB, 198/218 press moumed die The safety retract i actuated by the [51Int. Cl. 865g 25/04 press ram to remove the work gripping elements ofthe [58] Field Of Search 2l4/l BB; 198/218 transfer device from the dieshould the usual drive rangement for these elements be renderedinoperative.

[56] References Cited UNITED STATES PATENTS 19 Claims, 15 DrawingFigures 3,655,070 4/1972 Haydu 2l4/l BB Patented July 17, 1973 3,746,184

'7 Shoots-Sheet l w x 52 4 55 5a INVENTOR Y BERNHRD J. WHLLIS ATTORNEYSPatented July 17, 1973 9 104 INVENTOR BERNARD J. WALLIS W M, 7M

ATTORNEYS Patented Jul 17, 1973 3,746,184

7 Sheets-Sheet 5 INVENTOR BERNARD J. WALLIS BY v ,fl M 5 12 ATTORNEYSPatented July 17, 1973 3,746,184

7 SheetsShcet A 'FIG. 7

INVENTOR BERNARD J. WALLIS ATTORNEYS Patented July 17, 1973 7Sheets-Sheet 5 FIG. .71

BERNHRD J. WALLIS %WI W ATTORNEYS INVENTOR ATTORNEYS Patented July 17,1973- 7 Sheets-Sheet 6 "UT INS l s F u I a v BY BERNARD JWHLLIS SAFETYRETRACT MECHANISM This application is a continuation-in-part of my priorco-pending application Ser. No. 67,843, filed Aug. 28, 1970 and nowabandoned.

The present invention relates to a work transfer device for indexingworkpieces between successive stations in a die mounted in a press. Morespecifically, the invention is concerned with a safety retract mechanismfor positively removing the workpiece-engaging elements of the transferdevice from between the closing dies should the usual means forretracting these elements be rendered inoperative.

In my prior U.S. Pat. No. 3,411,636, issued Nov. 19, 1968, there isdisclosed a safety retract mechanism for a transfer device. An objectionto the operation of that mechanism is that the workpiece-engagingelements, also referred to as finger bars, cannot be retracted from theextended position so long as the carriage is in its forward transferstroke. Thus, should the carriage jam before the completion of thetransfer stroke the safety retract mechanism will be incapable ofretracting the finger bars.

In a transfer device in which the drive for the finger bars isindependent of the drive for the carriage, the finger bars can remainextended between the upper and lower dies should power to the finger bardrive be lost or should the fingerbars become disconnected from thedrive by the operation of an overload protection device. While anelectrical interlock for turning off the press should the finger barsremain in the extended position is often provided, the response of theram to the loss of drive signal may be relatively slow. Thus, should thesignal occur with the finger bars extended and the ram moving downward,the inertia of the ram may be sufficient to close the dies upon thefinger bars thereby damaging both the dies and the transfer device. Thissituation is especially critical when the press ram'has a short stroke.

It is an object of the present invention to provide a transfer devicehaving a safety retract mechanism which is actuated by the downwardmovement of the press ram for positively retracting the finger bars ofthe transfer device from between the closing dies should the usual drivearrangement for the finger bars be rendered inoperative either by anoverload condition in the transfer device or by a loss of power to thedrive by reason of a malfunction or other cause.

It is another object of this invention to provide a safety retractmechanism for the finger bars which operates independently of theposition of the carriage.

It is a further object of this invention to provide a safety retractmechanism which is integrated with existing components of the transferdevice so as to be of minimal cost.

In the drawings:

FIG. I is a plan view of a transfer device having a safety retractmechanism of the present invention.

FIG. 2 is a sectional view taken along line 2-2 in FIG. I.

FIG. 3 is a sectional view taken along line 33 in FIG. 2.

FIG. 4 is a sectional view taken along line 44 in FIG. 2.

FIG. 5 is a sectional view taken along line 5-5 in FIG. 1.

FIG. 6 is a plan view of the arrangement shown in FIG. 5.

FIG. 7 is a sectional view taken along line 77 in FIG. 6.

FIG. 8 is a sectional view taken along line 8-8 in FIG. 6. I

FIG. Q is a sectional view taken along line 99 in FIG. 1.

FIG. 10 is a plan view of the arrangement shown in FIG. 9.

FIG. 11 is a sectional view taken along line l111 in FIG. 10.

FIG. 12 is a sectional view taken along line l212 in FIG. 10.

FIG. 13 is a plan view of a transfer device embodying an alternativeform of the safety retract mechanism of the present invention.

FIG. 14 is a sectional view taken along line l4l4 in FIG. 13.

FIG. 15 is a sectional view taken along line 15l5 in FIG. 14.

Referring to FIG. 1, carriages 10, 10' are slidably mounted forrectilinear motion on bases 12,12 by means of guides 14. Finger bars 16,16' are slidably supported on carriages 10, 10' as well as on housings18, 18 for movement transverse to the direction of carriage travel.

The operating motion of finger bar 16 is described with reference to theindicated arrows, a, b, c, d, it being understood that the motion offinger bar 16 is symmetrically opposite. The cycle begins with fingerbar 16 being shifted in the direction of arrow a from the retractedposition to the extended position to thereby engage workpieces (notshown). Finger bar 16 carrying the workpieces in cooperation with fingerbar 16' is then transferred forward along arrow b by shifting carriage10. Having transferred the workpieces, finger bar 16 is now retractedalong arrow c, and is finally returned along the direction of arrowd toits initial position'by the return of carriage 10.

The drive mechanism for carriages 10, 10' and finger bars 16, 16,generally indicated at 20, comprises a motor and gear assembly 22adapted to rotate cam tracks 24, 26 about a pivot shaft 28. Cam track 24controls the transverse movement of finger bars 16, 16', while cam track26 controls the movement of carriages 10, 10'.

The finger bar motion is derived from a follower 30 trapped in track 24so as to reciprocate a gear rack 32. Rack 32 engages a pinion 34 whichis journalled on a shaft 36 and coupled to a sleeve 37 which forms theinput portion of an overload protection device 38. Overload protectiondevice 38 is similar to that described in my co-pending application Ser.No. 12,271, filed Feb. 18, 1970 (now U.S. Pat. No. 3,599,067, issuingAug. 10, I971 The output portion of device 38 includes shaft 36 whichextends between carriage l0 and housing 18 through sleeve 37. In theevent of an overload shaft 36 is uncoupled from sleeve 37. Shaft 36drives a pinion shaft 40 supported within housing 18 as is clearly shownin FIGS. 6 and 7. Pinion shaft '40 has a pinion 39 thereon (FIG. 6)which meshes with rack 42. Suitable gearing in carriage 10 connectsshaft 36 with rack 46. When shaft 36 is rotated in opposite directionsfinger bar 16, which is supported by the ends of racks 42, 46, isextended and retracted.

Pinion shaft 40 carries a second pinion 43 which meshes with a rack 44extending transversely between housings I8, 18'. Rack 44 provides adrive to finger bar 16' which is supported on the ends of racks 48, 50.Within housing 18', rack 44 meshes with a pinion 51 on one end of ashaft 54. Shaft 54 extends from housing 18 through carriage 10'. Asecond pinion 53 on shaft 54 drives rack 50 through a gear arrangementwhereby finger bars 16, 16' are extended and retracted in unison. Theconnection between shaft 54 and rack 48 is illustrated in FIGS. 9through 12. The portion of shaft 54 extending through carriage 10 issquare and is arranged to slide through a pinion S2 joumalled incarriage 10'. Pinion 52 meshes with rack 48. Thus, when rack 44 isreciprocated finger bar 16' is extended and retracted.

The carriage motion is derived from a follower S6 trapped in track 26and adapted to reciprocate a gear rack 58. Rack 58 in turn engagespinion 60 for rotating shaft 62. Shaft 62 is coupled to the inputportion of an overload device 64 which operates similarly to overloaddevice 38. The output portion of overload device 64 is adapted toreciprocate a rod 66 through gears 68, 70. Rod 66 is connected directlyto carriage l and has a second rack portion 67 within housing 18 fordriving a pinion sleeve 72 supported within housing 18, as is clearlyshown in FIGS. and 8. Pinion sleeve 72 is coupled to a coupling shaft 74which surrounds rack 44. Within housing 18 shaft 74 is connected by apinion (not shown) with a rack 75 connected directly to carriage Thuswhen shaft 62 is rotated carriages 10, 10' are shifted in unison. Ascarriage 10 and carriage 10' are shifted, finger bars 16, 16' areslidably guided through guide blocks 76, 76' which are supported fromhousings 18, 18'.

The safety retract mechanism of the present invention is shown generallyat 78 in FIG. 1. The mechanism comprises a rack 80 which meshes with apinion 82 and is slidable in a direction perpendicular to the directionof carriage travel as is clearly shown in FIGS. 2 and 4. Rack 80 isguided for movement on a base 84 by gibs 86 and has a chamfered endportion 94 which is adapted to be engaged by a cam 90 on the press ram92. Pinion 82 is coupled for rotation with sleeves 87, 88, which coupletogether the segments of finger bar actuating shaft 54.

Under normal operating conditions the finger bar actuating mechanismcauses pinion 82 to be rotated in a counter-clockwise direction in FIG.2 as finger bars 16, 16 are shifted from the extended position to theretracted position. This causes rack 80 to be shifted out of the way ofcam 90 which moves downward with ram 92. However, should there be amalfunction and the finger bars fail to be retracted from the path ofthe oncoming ram, rack 80 remains disposed in the path of cam 90. As theram continues downward cam 90 engages rack 80 as shown by the brokenlines in FIG. 2. As the ram completes its downward stroke, the action ofcam 90 with the chamfered portion 94 of rack 80 shifts rack 80 out ofthe path of the cam. As rack 80 is shifted, it rotates pinion 82 tothereby retract finger bars 16, 16'. Thus, the finger bars arepositively removed from between the closing dies so as to prevent anydamage thereto regardless of the position of carriages 10, 10.

An alternative form of the safety retract mechanism is shown generallyat 100 in FIG. 13. The drive shaft 102 of the transfer device 104 isadapted to drive the carriage 106 as well as to actuate the finger bars108, 108'. The carriage motion is derived from a cam track 110 whichactuates a lever 112 for pivotal movement about shaft 114. The oppositeend of lever 112 is adapted to shift drive shaft 102 for transferringcarriage 106 by means of a collar 116 axially fixed to shaft 102 and inwhich shaft 102 is free to rotate. The finger bar motion is derived froma cam track 118 which rotates shaft 102 by means ofa gear 120 and a rack121. Shaft 102 is free to slide through gear 120 during carriagetransfer but is keyed to gear 120 for rotation therewith.

Safety retract mechanism 100 is fixably mounted on transfer device 104,and comprises a pinion 122 which is adapted to be rotated by shaft 102(FIGS. 14 and 15), and through which shaft 102 is free to slide duringcarriage transfer. Pinion 122 meshes with a second pinion 124 to whichis attached a crank 126. A roller 128 at the end of crank 126 is adaptedto be engaged by an actuator 130 attached to the press ram.

Under normal operation, as the finger bars are shifted by the rotationof shaft 102 pinion 122 is also rotated. This causes crank 126 to bepivoted out of the path of actuator 130 as the ram completes it downstroke. In the event of a malfunction causing the finger bars to remainextended with the ram moving downward, actuator 130 engages crank 126 asshown by the broken lines in FIG. 14. As the ram continues downwardcrank 126 is pivoted by actuator 130 so as to rotate shaft 102 throughpinions 122, 124 and thereby positively remove the finger bars frombetween the closing dies.

In the arrangement shown in FIG. 13 a safety overload disconnectmechanism would be connected be tween shaft 132 which drives the cam onwhich cam tracks 110, 118 are formed and the mechanism for driving shaft132 to disconnect the drive to the carriage in the event that it jams inthe course of its longitudinal stroke. An additional safety overloaddisconnect mechanism would also be located in the rotary drive betweenthe cam and shaft 102 to permit the cam to continue to rotate in theevent the finger bars 108, 108' jam in the course of their transversemovement.

It will be noted with respect to both embodiments illustrated that thedrive for the finger bars operates independently of the drive to thecarriages, and thus, even if the carriages should jam at any point intheir stroke, the safety retract mechanisms are adapted to retract thefinger bars.

It will also be appreciated that the gear and rack arrangement shown inFIG. 2 and the gear and crank arrangement shown in FIG. 14 are merelyoptional de vices for rotation the finger bar actuating shaft and are,thus, interchangeable regardless of whether the finger bar actuatingshaft merely rotates or rotates and shafts axially.

I claim:

I. In a transfer device for use with a press having a verticallyreciprocating ram on which an upper die is adapted to be mounted forcooperation with a lower die, said device being of the type fortransferring a workpiece between stations in the die and having a carriage shiftable rectilinearly between a return position and a forwardposition and on which is slidably supported a finger bar shiftablebetween an extended, workpiece-engaging position and a retractedposition in a direction generally transverse to the direction of travelof the carriage, the combination comprising first drive means, meansoperatively connecting said first drive means with said carriage forshifting the carriage,

means operable independently of said last-mentioned means operativelyconnecting said first drive means with said finger bar for shifting thefinger bar, control means for shifting the carriage and the finger barin a predetermined sequence, a safety retract mechanism comprising asecond drive means, means including a rotatable shaft operativelyconnecting the second drive means with the finger bar for shifting thefinger bar, and means responsive to the downward movement of said pressram with the finger bar in the extended position for rotating saidrotatable shaft to shift the finger bar to the retracted positionindependent of the position of the carriage.

2. The combination called for in claim 1 wherein said means for rotatingsaid rotatable shaft is movable with the press ram.

3. The combination called for in claim 1 wherein said operativeconnection between said first drive means and said carriage comprises ashaft which is axially movable and fixedly connected to the carriage,said rotatable shaft being common to said two operative connectionsbetween the finger bar and the first and second drive means, saidrotatable shaft being rotatable independently of axial movement of saidaxially movable shaft to shift said finger bar.

4. The combination called for in claim 3 including means fordisconnecting said common shaft from the first drive means in the eventthe torque on said shaft exceeds a predetermined value.

5. The combination called for in claim 2 wherein said second drive meansincludes a movable member operably connected to said rotatable shaft andlying in the path of travel of the means for rotating said shaft whenthe finger bar is in the extended position, said actuating means beingadapted to engage and move said movable member to retract the finger barwhen the press ram descends to a predetermined position with the fingerbar in the extended position.

6. The combination called for in claim 5 wherein said movable membercomprises a crank.

7. The combination called for in claim 6 wherein said operativeconnection between said first mentioned drive means and said carriagecomprises a shaft which is axially movable and fixedly connected to thecarriage, said two operative connections between the finger bar and thefirst and second drive means including said rotatable shaft, saidrotatable shaft being rotatable independently of axial movement of saidaxially movable shaft to shift said finger bar, said crank beingoperatively connected with said shaft.

8. The combination called for in claim 5 wherein said movable membercomprises a gear rack.

9. The combination called for in claim 8 wherein said actuating meansincludes cam means adapted to move said gear rack.

I0. The combination called for in claim 8 wherein said operativeconnection between said first mentioned drive means and said carriagecomprises a shaft which is axially movable and fixedly connected to thecarriage, said two operative connections between the finger bar and thefirst and second drive means including said rotatable shaft, saidrotatable shaft being rotatable independently of axial movement of saidaxially movable shaft to shift said finger bar, and said gear rack beingoperatively connected with said shaft.

1]. In a transfer device for use with a press having a verticallyreciprocating ram on which an upper die is adapted to be mounted forcooperation with a lower die, said device being of the type fortransferring a workpiece between stations in the die and having acarriage shiftable rectilinearly between a return position and a forwardposition and on which is supported a finger bar shiftable in a directiongenerally transverse to the direction of travel of the carriage betweenan extended workpiece-engaging position and a retracted position, thecombination comprising, first drive means for the transfer device, meansforming a first drive train operatively connecting said first drivemeans with said carriage for shifting the carriage, means forming asecond drive train operatively connecting said drive means with saidfinger bar for shifting the finger bar, means in and individual to saidlast-mentioned drive train forming an overload disconnect therein foroperatively disconnecting said finger bar from said drive means when thedriving force to which the second drive train is subjected exceeds apredetermined value, a rotatable shaft which when actuated is adapted toshift the finger bar independently of the overload disconnect means, asafety retract mechanism for the finger bar comprising a second drivemeans, means operatively connecting the second drive means with saidrotatable shaft for shifting the finger bar, and means timed with thedownward movement of said press ram for actuating said last-mentioneddrive means to actuate said rotatable shaft and shift the finger bar tothe retracted position in the event the first drive means is ineffectiveto re tract the finger bar.

12. The combination called for in claim 11 wherein said rotatable shaftcomprises an element of thesecond drive train located therein betweenthe overload disconnect means and the finger bar.

13. The combination called for in claim 11 wherein the means foractuating the second drive means are adapted to reciprocate with thepress ram and to actuate the second drive means upon downward movementof the press ram.

14. The combination called for in claim 11 wherein said rotatable shaftforms an element of the second drive train.

15. The combination called for in claim 11 wherein the actuating meansfor the second drive means are mounted to move the press ram, the seconddrive means including a movable member which lies in the path of travelof the actuating means when thefinger bar is in the extended or partlyextended position, said actuating means being adapted to engage and movesaid movable member to retract the finger bar when the press ramdescends to a predetermined position and the finger bar is in theextended or partly extended position.

16. The combination called for in claim 15 wherein the movable membercomprises a crank.

17. The combination called for in claim 15 wherein the movable membercomprises a gear rack.

18. The combination called for in claim 17 wherein the actuating meansincludes a cam for moving said gear rack.

19. In a transfer device for use with a press having a verticallyreciprocating ram on which an upper die is adapted to be mounted forcooperation with a lower die, said device being of the type fortransferring a workpiece between a series of successive stations in thedie and having work-engaging fingers thereon shiftable betweensuccessive stations in forward and return strokes for advancing theworkpieces to successive stations and shiftable in a directiontransversely of said stations between an extended work-engaging positionand a retracted position, said device including a finger bar member anda carriage member, said workengaging fingers being mounted on the fingerbar member and said finger bar member being mounted on the carriagemember, means for guiding one of said members in a path parallel to theseries of stations to shift the work-engaging fingers in said forwardand return strokes, means for guiding the other member in a pathtransversely of said series of stations for shifting the work-engagingfingers to said work-engaging position and said retracted positionwhereby, when said members are shifted in a predetermined sequence intheir respective paths of travel, the work-engaging fingers are firstcaused to shift into work-engaging position, then moved forwardly in theadvance stroke to advance the engaged workpieces to the next successivestations, then retracted to disengage the workpieces and finally movedin the return stroke to return the work-engaging fingers to the startingposition, the combination comprising, first drive means for the transferdevice, means forming a first drive train operatively connecting saidfirst drive means with said one member for shifting the work-engagingfingers between successive stations, means forming a second drive trainoperatively connecting said first drive means with said other member forshifting the work-engaging fingers between work engaging and retractedpositions, means in and individual to said last-mentioned drive trainforming an overload disconnect therein for operatively disconnectingsaid other member for shifting the work-engaging fingers to and fromwork-engaging position from the first drive means when the driving forceto which the second drive train is subjected exceeds a predeterminedvalue, a rotatable shaft which when actuated is adapted to shift thework-engaging fingers to the retracted position independently of thecondition of the overload disconnect means, a safety retract mechanismfor the work engaging fingers comprising, a second drive means, meansoperatively connecting the second drive means with said rotatable shaftand means timed with the downward movement of the press ram foractuating the lastrnentioned drive means to in turn actuate saidrotatable shaft and shift the work-engaging fingers to the retractedposition in the event the first drive means is ineffective toretract thework-engaging fingers.

1. In a transfer device for use with a press having a verticallyreciprocating ram on which an upper die is adapted to be mounted forcooperation with a lower die, said device being of the type fortransferring a workpiece between stations in the die and having acarriage shiftable rectilinearly between a return position and a forwardposition and on which is slidably supported a finger bar shiftablebetween an extended, workpieceengaging position and a retracted positionin a direction generally transverse to the direction of travel of thecarriage, the combination comprising first drive means, meansoperatively connecting said first drive means with said carriage forshifting the carriage, means operable independently of saidlast-mentioned means operatively connecting said first drive means withsaid finger bar for shifting the finger bar, control means for shiftingthe carriage and the finger bar in a predetermined sequence, a safetyretract mechanism comprising a second drive means, means including arotatable shaft operatively connecting the second drive means with thefinger bar for shifting the finger bar, and means responsive to thedownward movement of said press ram with the finger bar in the extendedposition for rotating said rotatable shaft to shift the finger bar tothe retracted position independent of the position of the carriage. 2.The combination called for in claim 1 wherein said means for rotatingsaid rotatable shaft is movable with the press ram.
 3. The combinationcalled for in claim 1 wherein said operative connection between saidfirst drive means and said carriage comprises a shaft which is axiallymovable and fixedly connected to the carriage, said rotatable shaftbeing common to said two operative connections between the finger barand the first and second drive means, said rotatable shaft beingrotatable independently of axial movement of said axially movable shaftto shift said finger bar.
 4. The combination called for in claim 3including means for disconnecting said common shaft from the first drivemeans in the event the torque on said shaft exceeds a predeterminedvalue.
 5. The combination called for in claim 2 wherein said seconddrive means includes a movable member operably connected to saidrotatable shaft and lying in the path of travel of the means forrotating said shaft when the finger bar is in the extended position,said actuating means being adapted to engage and move said movablemember to retract the finger bar when the press ram descends to apredetermined position with the finger bar in the extended position. 6.The combination called for in claim 5 wherein said movable membercomprises a crank.
 7. The combination called for in claim 6 wherein saidoperative connection between said first mentioned drive means and saidcarriage comprises a shaft which is axially movable and fixedlyconnected to the carriage, said two operative connections between thefinger bar and the first and second drive means including said rotatableshaft, said rotatable shaft being rotatable independently of axialmovement of said axially movable shaft to shift said finger bar, saidcrank being operatively connected with said shaft.
 8. The combinationcalled for in claim 5 wherein said movable member comprises a gear rack.9. The combination called for in claim 8 wherein said actuating meansincludes cam means adapted to move said gear rack.
 10. The combinationcalled for in claim 8 wherein said operative connection between saidfirst mentioned drive means and said carriage comprises a shaft which isaxially movable and fixedly connected to the carriage, said twooperative connections between the finger bar and the first and seconddrive means including said rotatable shaft, said rotatable shaft beingrotatable independently of axial movement of said axially movable shaftto shift said finger bar, and said gear rack being operatively connectedwith said shaft.
 11. In a transfer device for use with a press having avertically reciprocating ram on which an upper die is adapted to bemounted for cooperation with a lower die, said device being of the typefor transferring a workpiece between stations in the die and having acarriage shiftable rectilinearly between a return position and a forwardposition and on which is supported a finger bar shiftable in a directiongenerally transverse to the direction of travel of the carriage betweenan extended workpiece-engaging position and a retracted position, thecombination comprising, first drive means for the transfer device, meansforming a first drive train operatively connecting said first drivemeans with said carriage for shifting the carriage, means forming asecond drive train operatively connecting said drive means with saidfinger bar for shifting the finger bar, means in and individual to saidlast-mentioned drive train forming an overload disconnect therein foroperatively disconnecting said finger bar from said drive means when thedriving force to which the second drive train is subjected exceeds apredetermined value, a rotatable shaft which when actuated is adapted toshift the finger bar independently of the overload disconnect means, asafety retract mechanism for the finger bar comprising a second drivemeans, means operatively connecting the second drive means with saidrotatable shaft for shifting the finger bar, and means timed with thedownward movement of said press ram for actuating said last-mentioneddrive means to actuate said rotatable shaft and shift the finger bar tothe retracted position in the event the first drive means is ineffectiveto retract the finger bar.
 12. The combination called for in claim 11wherein said rotatable shaft comprises an element of the second drivetrain located therein between the overload disconnect means and thefinger bar.
 13. The combination called for in claim 11 wherein the meansfor actuating the second drive means are adapted to reciprocate with thepress ram and to actuate the second drive means upon downward movementof the press ram.
 14. The combination called for in claim 11 whereinsaid rotatable shaft forms an element of the second drive train.
 15. Thecombination called for in claim 11 wherein the actuating means for thesecond drive means are mounted to move the press ram, the second drivemeans including a movable member which lies in the path of travel of theactuating means when the finger bar is in the extended or partlyextended position, said actuating means being adapted to engage and movesaid movable member to retract the finger bar when the press ramdescends to a predetermined position and the finger bar is in theextended or partly extended position.
 16. The combination called for inclaim 15 wherein the movable member comprises a crank.
 17. Thecombination called for in claim 15 wherein the movable member comprisesa gear rack.
 18. The combination called for in claim 17 wherein theactuating means includes a cam for moving said gear rack.
 19. In atransfer device for use with a press having a vertically reciprocatingram on which an upper die is adapted to be mounted for cooperation witha lower die, said device being of the type for transferring a workpiecebetween a series of successive stations in the die and havingwork-engaging fingers thereon shiftable between successive stations inforward and return strokes for advancing the workpieces to successivestations and shiftable in a direction transversely of said stationsbetween an extended work-engaging position and a retracted position,said device including a finger bar member and a carriage member, saidwork-engaging fingers being mounted on the finger bar member and saidfinger bar member being mounted on the carriage member, means forguiding one of said members in a path parallel to the series of stationsto shift the work-engaging fingers in said forward and return strokes,means for guiding the other member in a path transversely of said seriesof stations for shifting the work-engaging fingers to said work-engagingposition and said retracted position whereby, when said members areshifted in a predetermined sequence in their respective paths of travel,the work-engaging fingers are first caused to shift into work-engagingposition, then moved forwardly in the advance stroke to advance theengaged workpieces to the next successive stations, then retracted todisengage the workpieces and finally moved in the return stroke toreturn the work-engaging fingers to the starting position, thecombination comprising, first drive means for the transfer device, meansforming a first drive train operatively connecting said first drivemeans with said one member for shifting the work-engaging fingersbetween successive stations, means forming a second drive trainoperatively connecting said first drive means with said other member forshifting the work-engaging fingers between work-engaging and retractedpositions, means in and individual to said last-mentioned drive trainforming an overload disconnect therein for operatively disconnectingsaid other member for shifting the work-engaging fingers to and fromwork-engaging position from the first drive means when the driving forceto which the second drive train is subjected exceeds a predeterminedvalue, a rotatable shaft which when actuated is adapted to shift thework-engaging fingers to the retracted position independently of thecondition of the overload disconnect means, a safety retract mechanismfor the work-engaging fingers comprising, a second drive means, meansoperatively connecting the second drive means with said rotatable shaftand means timed with the downward movement of the press ram foractuating the lastmentioned drive means to in turn actuate saidrotatable shaft and shift the work-engaging fingers to the retractedposition in the event the first drive means is ineffective to retractthe work-engaging fingers.